The next Archbishop of Canterbury has staked his authority on a yes vote by the General Synod to legislation introducing the first women bishops.

The Rt Rev Justin Welby, Bishop of Durham, told the General Synod on Tuesday that it was "time to finish the job" and vote in favour of final approval for legislation paving the way for the first women bishops.

He pledged to support traditionalists who oppose the ordination of women but said the ministry of women as priests had been "powerful" in all areas of the Church of England apart from the episcopacy.

"It is time to finish the job and vote for this measure but also the Church of England needs to show how we can develop the mission of the Church in a way that demonstrates that we can manage diversity of view without division - diversity in amity, not diversity in enmity," he said.

He added: "I am personally deeply committed and believe that fellow bishops are also to ensuring as far as I am able that all that we promise today and later in the code of conduct is carried out faithfully in spirit as well as in letter.

"Expressing in attitude and by our actions that we more than respect but also love one another is a foundation stone of our mission in this country and the world more widely.

The Bishop of Durham, Justin Welby, is in favour of women bishops

"We cannot get trapped into believing this is a zero-sum decision where one person's gain must be another's loss. That is not a theology of grace."

The Rt Rev Welby was backed by the Archbishop of Canterbury Dr Rowan Williams, who leaves his post after a decade in office at the end of the year.

He told the General Synod he believed it was time to "turn a page".

"I am rather clearer that a no vote would not do anything positive for our mission in this country," he said.

"I do believe that it is time to turn a page and discover what we can actually do with this," he added.

The Reverend Janet Appleby addresses the General Synod during the debate on Tuesday

The intervention of both clerics come as the General Synod prepared to vote on whether to give final approval to the legislation after years of debate.

The move is the biggest decision to be taken by the 470-strong body in 20 years and comes amid protests from traditionalists who oppose the ordination of women.

The call by both Dr Williams and Bishop Welby comes after the Rt Rev Nigel McCulloch, Bishop of Manchester, warned of the "devastating" blow to morale if the legislation fails to be given final approval.

He said the measure before the General Synod had imperfections and there were "understandable" concerns from those opposed to the ordination of women.

But he said he believed the legislation would allow the Church of England to flourish and enable women to exercise leadership, which many recognised as "God's gift" to the Church.

Failing to allow the legislation to clear its final hurdle would do "real harm" to the credibility and mission of the Church of England to the people of this nation, he said.

"If today's legislation goes down after all the work and hopes of the past few years, it would be a shock to a large number of people across the Church of England," he told the General Synod.

"It would be a devastating blow to the morale of many, not least our female clergy. It would be a major deterrent to continuing to attract into the ordained ministry able women - and many able men too," he said.

But Canon Simon Killwick, a vicar in Moss Side, Manchester, in the Rt Rev McCulloch's diocese, and chairman of the Catholic Group in the General Synod, urged members to vote against the legislation.

"I do not believe that this draft legislation will be good for the Church of England," he said.

"We are all desperate to move on from the sad infighting of the last few years - but this legislation does not provide a clear way forward."

Under the legislation, a woman bishop would delegate to a stand-in male bishop to minister to parishes which rejected her authority, using a code of practice for guidance.

The Rev Prebendary Rod Thomas, chairman of the conservative evangelical group Reform and a vicar in Plymouth, said they would be forced to accept the authority of a woman bishop under the legislation.

"We have to accept that authority because even when we get the alternative bishop through the diocesan scheme - the one that we have to accept is a delegate of the female bishop, so all along the line we are accepting the authority of a woman bishop. We are required to accept something that we don't believe the Bible teaches," he said.

But the Rev Canon Rosie Harper, from the Oxford Diocese, said the Church would be seen to have "failed" it did not back the legislation.

"We will seen to have failed to do what is right and honourable - a Church with lower moral standards than the rest of society loses its right to comment on other issues, it will inevitably be seen as an act of a dying Church," she said.

She added that failing to clear the final hurdle would be seen as a "vote of no confidence" in Dr Williams and Bishop Welby.

The Bishop of Liverpool, the Rt Rev James Jones, backed giving the legislation final approval.

"The truth is that without women in leadership we are no longer able to serve the people in the parishes of England, women serve as leaders in scripture, on the mission field and as supreme governor and in this General Synod," he said.

"I now believe that for the mission of God to the people of England it is right for women to take up their place in this House of Bishops sitting before you now."